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Diffstat (limited to '3rdparty/SDL2/src/audio/SDL_audiocvt.c')
-rw-r--r--3rdparty/SDL2/src/audio/SDL_audiocvt.c1121
1 files changed, 0 insertions, 1121 deletions
diff --git a/3rdparty/SDL2/src/audio/SDL_audiocvt.c b/3rdparty/SDL2/src/audio/SDL_audiocvt.c
deleted file mode 100644
index 3b47c4cbcc0..00000000000
--- a/3rdparty/SDL2/src/audio/SDL_audiocvt.c
+++ /dev/null
@@ -1,1121 +0,0 @@
-/*
- Simple DirectMedia Layer
- Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
-
- This software is provided 'as-is', without any express or implied
- warranty. In no event will the authors be held liable for any damages
- arising from the use of this software.
-
- Permission is granted to anyone to use this software for any purpose,
- including commercial applications, and to alter it and redistribute it
- freely, subject to the following restrictions:
-
- 1. The origin of this software must not be misrepresented; you must not
- claim that you wrote the original software. If you use this software
- in a product, an acknowledgment in the product documentation would be
- appreciated but is not required.
- 2. Altered source versions must be plainly marked as such, and must not be
- misrepresented as being the original software.
- 3. This notice may not be removed or altered from any source distribution.
-*/
-#include "../SDL_internal.h"
-
-/* Functions for audio drivers to perform runtime conversion of audio format */
-
-#include "SDL_audio.h"
-#include "SDL_audio_c.h"
-
-#include "SDL_assert.h"
-
-/* #define DEBUG_CONVERT */
-
-/* Effectively mix right and left channels into a single channel */
-static void SDLCALL
-SDL_ConvertMono(SDL_AudioCVT * cvt, SDL_AudioFormat format)
-{
- int i;
- Sint32 sample;
-
-#ifdef DEBUG_CONVERT
- fprintf(stderr, "Converting to mono\n");
-#endif
- switch (format & (SDL_AUDIO_MASK_SIGNED |
- SDL_AUDIO_MASK_BITSIZE |
- SDL_AUDIO_MASK_DATATYPE)) {
- case AUDIO_U8:
- {
- Uint8 *src, *dst;
-
- src = cvt->buf;
- dst = cvt->buf;
- for (i = cvt->len_cvt / 2; i; --i) {
- sample = src[0] + src[1];
- *dst = (Uint8) (sample / 2);
- src += 2;
- dst += 1;
- }
- }
- break;
-
- case AUDIO_S8:
- {
- Sint8 *src, *dst;
-
- src = (Sint8 *) cvt->buf;
- dst = (Sint8 *) cvt->buf;
- for (i = cvt->len_cvt / 2; i; --i) {
- sample = src[0] + src[1];
- *dst = (Sint8) (sample / 2);
- src += 2;
- dst += 1;
- }
- }
- break;
-
- case AUDIO_U16:
- {
- Uint8 *src, *dst;
-
- src = cvt->buf;
- dst = cvt->buf;
- if (SDL_AUDIO_ISBIGENDIAN(format)) {
- for (i = cvt->len_cvt / 4; i; --i) {
- sample = (Uint16) ((src[0] << 8) | src[1]) +
- (Uint16) ((src[2] << 8) | src[3]);
- sample /= 2;
- dst[1] = (sample & 0xFF);
- sample >>= 8;
- dst[0] = (sample & 0xFF);
- src += 4;
- dst += 2;
- }
- } else {
- for (i = cvt->len_cvt / 4; i; --i) {
- sample = (Uint16) ((src[1] << 8) | src[0]) +
- (Uint16) ((src[3] << 8) | src[2]);
- sample /= 2;
- dst[0] = (sample & 0xFF);
- sample >>= 8;
- dst[1] = (sample & 0xFF);
- src += 4;
- dst += 2;
- }
- }
- }
- break;
-
- case AUDIO_S16:
- {
- Uint8 *src, *dst;
-
- src = cvt->buf;
- dst = cvt->buf;
- if (SDL_AUDIO_ISBIGENDIAN(format)) {
- for (i = cvt->len_cvt / 4; i; --i) {
- sample = (Sint16) ((src[0] << 8) | src[1]) +
- (Sint16) ((src[2] << 8) | src[3]);
- sample /= 2;
- dst[1] = (sample & 0xFF);
- sample >>= 8;
- dst[0] = (sample & 0xFF);
- src += 4;
- dst += 2;
- }
- } else {
- for (i = cvt->len_cvt / 4; i; --i) {
- sample = (Sint16) ((src[1] << 8) | src[0]) +
- (Sint16) ((src[3] << 8) | src[2]);
- sample /= 2;
- dst[0] = (sample & 0xFF);
- sample >>= 8;
- dst[1] = (sample & 0xFF);
- src += 4;
- dst += 2;
- }
- }
- }
- break;
-
- case AUDIO_S32:
- {
- const Uint32 *src = (const Uint32 *) cvt->buf;
- Uint32 *dst = (Uint32 *) cvt->buf;
- if (SDL_AUDIO_ISBIGENDIAN(format)) {
- for (i = cvt->len_cvt / 8; i; --i, src += 2) {
- const Sint64 added =
- (((Sint64) (Sint32) SDL_SwapBE32(src[0])) +
- ((Sint64) (Sint32) SDL_SwapBE32(src[1])));
- *(dst++) = SDL_SwapBE32((Uint32) ((Sint32) (added / 2)));
- }
- } else {
- for (i = cvt->len_cvt / 8; i; --i, src += 2) {
- const Sint64 added =
- (((Sint64) (Sint32) SDL_SwapLE32(src[0])) +
- ((Sint64) (Sint32) SDL_SwapLE32(src[1])));
- *(dst++) = SDL_SwapLE32((Uint32) ((Sint32) (added / 2)));
- }
- }
- }
- break;
-
- case AUDIO_F32:
- {
- const float *src = (const float *) cvt->buf;
- float *dst = (float *) cvt->buf;
- if (SDL_AUDIO_ISBIGENDIAN(format)) {
- for (i = cvt->len_cvt / 8; i; --i, src += 2) {
- const float src1 = SDL_SwapFloatBE(src[0]);
- const float src2 = SDL_SwapFloatBE(src[1]);
- const double added = ((double) src1) + ((double) src2);
- const float halved = (float) (added * 0.5);
- *(dst++) = SDL_SwapFloatBE(halved);
- }
- } else {
- for (i = cvt->len_cvt / 8; i; --i, src += 2) {
- const float src1 = SDL_SwapFloatLE(src[0]);
- const float src2 = SDL_SwapFloatLE(src[1]);
- const double added = ((double) src1) + ((double) src2);
- const float halved = (float) (added * 0.5);
- *(dst++) = SDL_SwapFloatLE(halved);
- }
- }
- }
- break;
- }
-
- cvt->len_cvt /= 2;
- if (cvt->filters[++cvt->filter_index]) {
- cvt->filters[cvt->filter_index] (cvt, format);
- }
-}
-
-
-/* Discard top 4 channels */
-static void SDLCALL
-SDL_ConvertStrip(SDL_AudioCVT * cvt, SDL_AudioFormat format)
-{
- int i;
-
-#ifdef DEBUG_CONVERT
- fprintf(stderr, "Converting down from 6 channels to stereo\n");
-#endif
-
-#define strip_chans_6_to_2(type) \
- { \
- const type *src = (const type *) cvt->buf; \
- type *dst = (type *) cvt->buf; \
- for (i = cvt->len_cvt / (sizeof (type) * 6); i; --i) { \
- dst[0] = src[0]; \
- dst[1] = src[1]; \
- src += 6; \
- dst += 2; \
- } \
- }
-
- /* this function only cares about typesize, and data as a block of bits. */
- switch (SDL_AUDIO_BITSIZE(format)) {
- case 8:
- strip_chans_6_to_2(Uint8);
- break;
- case 16:
- strip_chans_6_to_2(Uint16);
- break;
- case 32:
- strip_chans_6_to_2(Uint32);
- break;
- }
-
-#undef strip_chans_6_to_2
-
- cvt->len_cvt /= 3;
- if (cvt->filters[++cvt->filter_index]) {
- cvt->filters[cvt->filter_index] (cvt, format);
- }
-}
-
-
-/* Discard top 2 channels of 6 */
-static void SDLCALL
-SDL_ConvertStrip_2(SDL_AudioCVT * cvt, SDL_AudioFormat format)
-{
- int i;
-
-#ifdef DEBUG_CONVERT
- fprintf(stderr, "Converting 6 down to quad\n");
-#endif
-
-#define strip_chans_6_to_4(type) \
- { \
- const type *src = (const type *) cvt->buf; \
- type *dst = (type *) cvt->buf; \
- for (i = cvt->len_cvt / (sizeof (type) * 6); i; --i) { \
- dst[0] = src[0]; \
- dst[1] = src[1]; \
- dst[2] = src[2]; \
- dst[3] = src[3]; \
- src += 6; \
- dst += 4; \
- } \
- }
-
- /* this function only cares about typesize, and data as a block of bits. */
- switch (SDL_AUDIO_BITSIZE(format)) {
- case 8:
- strip_chans_6_to_4(Uint8);
- break;
- case 16:
- strip_chans_6_to_4(Uint16);
- break;
- case 32:
- strip_chans_6_to_4(Uint32);
- break;
- }
-
-#undef strip_chans_6_to_4
-
- cvt->len_cvt /= 6;
- cvt->len_cvt *= 4;
- if (cvt->filters[++cvt->filter_index]) {
- cvt->filters[cvt->filter_index] (cvt, format);
- }
-}
-
-/* Duplicate a mono channel to both stereo channels */
-static void SDLCALL
-SDL_ConvertStereo(SDL_AudioCVT * cvt, SDL_AudioFormat format)
-{
- int i;
-
-#ifdef DEBUG_CONVERT
- fprintf(stderr, "Converting to stereo\n");
-#endif
-
-#define dup_chans_1_to_2(type) \
- { \
- const type *src = (const type *) (cvt->buf + cvt->len_cvt); \
- type *dst = (type *) (cvt->buf + cvt->len_cvt * 2); \
- for (i = cvt->len_cvt / sizeof(type); i; --i) { \
- src -= 1; \
- dst -= 2; \
- dst[0] = dst[1] = *src; \
- } \
- }
-
- /* this function only cares about typesize, and data as a block of bits. */
- switch (SDL_AUDIO_BITSIZE(format)) {
- case 8:
- dup_chans_1_to_2(Uint8);
- break;
- case 16:
- dup_chans_1_to_2(Uint16);
- break;
- case 32:
- dup_chans_1_to_2(Uint32);
- break;
- }
-
-#undef dup_chans_1_to_2
-
- cvt->len_cvt *= 2;
- if (cvt->filters[++cvt->filter_index]) {
- cvt->filters[cvt->filter_index] (cvt, format);
- }
-}
-
-
-/* Duplicate a stereo channel to a pseudo-5.1 stream */
-static void SDLCALL
-SDL_ConvertSurround(SDL_AudioCVT * cvt, SDL_AudioFormat format)
-{
- int i;
-
-#ifdef DEBUG_CONVERT
- fprintf(stderr, "Converting stereo to surround\n");
-#endif
-
- switch (format & (SDL_AUDIO_MASK_SIGNED |
- SDL_AUDIO_MASK_BITSIZE |
- SDL_AUDIO_MASK_DATATYPE)) {
- case AUDIO_U8:
- {
- Uint8 *src, *dst, lf, rf, ce;
-
- src = (Uint8 *) (cvt->buf + cvt->len_cvt);
- dst = (Uint8 *) (cvt->buf + cvt->len_cvt * 3);
- for (i = cvt->len_cvt; i; --i) {
- dst -= 6;
- src -= 2;
- lf = src[0];
- rf = src[1];
- ce = (lf / 2) + (rf / 2);
- dst[0] = lf;
- dst[1] = rf;
- dst[2] = lf - ce;
- dst[3] = rf - ce;
- dst[4] = ce;
- dst[5] = ce;
- }
- }
- break;
-
- case AUDIO_S8:
- {
- Sint8 *src, *dst, lf, rf, ce;
-
- src = (Sint8 *) cvt->buf + cvt->len_cvt;
- dst = (Sint8 *) cvt->buf + cvt->len_cvt * 3;
- for (i = cvt->len_cvt; i; --i) {
- dst -= 6;
- src -= 2;
- lf = src[0];
- rf = src[1];
- ce = (lf / 2) + (rf / 2);
- dst[0] = lf;
- dst[1] = rf;
- dst[2] = lf - ce;
- dst[3] = rf - ce;
- dst[4] = ce;
- dst[5] = ce;
- }
- }
- break;
-
- case AUDIO_U16:
- {
- Uint8 *src, *dst;
- Uint16 lf, rf, ce, lr, rr;
-
- src = cvt->buf + cvt->len_cvt;
- dst = cvt->buf + cvt->len_cvt * 3;
-
- if (SDL_AUDIO_ISBIGENDIAN(format)) {
- for (i = cvt->len_cvt / 4; i; --i) {
- dst -= 12;
- src -= 4;
- lf = (Uint16) ((src[0] << 8) | src[1]);
- rf = (Uint16) ((src[2] << 8) | src[3]);
- ce = (lf / 2) + (rf / 2);
- rr = lf - ce;
- lr = rf - ce;
- dst[1] = (lf & 0xFF);
- dst[0] = ((lf >> 8) & 0xFF);
- dst[3] = (rf & 0xFF);
- dst[2] = ((rf >> 8) & 0xFF);
-
- dst[1 + 4] = (lr & 0xFF);
- dst[0 + 4] = ((lr >> 8) & 0xFF);
- dst[3 + 4] = (rr & 0xFF);
- dst[2 + 4] = ((rr >> 8) & 0xFF);
-
- dst[1 + 8] = (ce & 0xFF);
- dst[0 + 8] = ((ce >> 8) & 0xFF);
- dst[3 + 8] = (ce & 0xFF);
- dst[2 + 8] = ((ce >> 8) & 0xFF);
- }
- } else {
- for (i = cvt->len_cvt / 4; i; --i) {
- dst -= 12;
- src -= 4;
- lf = (Uint16) ((src[1] << 8) | src[0]);
- rf = (Uint16) ((src[3] << 8) | src[2]);
- ce = (lf / 2) + (rf / 2);
- rr = lf - ce;
- lr = rf - ce;
- dst[0] = (lf & 0xFF);
- dst[1] = ((lf >> 8) & 0xFF);
- dst[2] = (rf & 0xFF);
- dst[3] = ((rf >> 8) & 0xFF);
-
- dst[0 + 4] = (lr & 0xFF);
- dst[1 + 4] = ((lr >> 8) & 0xFF);
- dst[2 + 4] = (rr & 0xFF);
- dst[3 + 4] = ((rr >> 8) & 0xFF);
-
- dst[0 + 8] = (ce & 0xFF);
- dst[1 + 8] = ((ce >> 8) & 0xFF);
- dst[2 + 8] = (ce & 0xFF);
- dst[3 + 8] = ((ce >> 8) & 0xFF);
- }
- }
- }
- break;
-
- case AUDIO_S16:
- {
- Uint8 *src, *dst;
- Sint16 lf, rf, ce, lr, rr;
-
- src = cvt->buf + cvt->len_cvt;
- dst = cvt->buf + cvt->len_cvt * 3;
-
- if (SDL_AUDIO_ISBIGENDIAN(format)) {
- for (i = cvt->len_cvt / 4; i; --i) {
- dst -= 12;
- src -= 4;
- lf = (Sint16) ((src[0] << 8) | src[1]);
- rf = (Sint16) ((src[2] << 8) | src[3]);
- ce = (lf / 2) + (rf / 2);
- rr = lf - ce;
- lr = rf - ce;
- dst[1] = (lf & 0xFF);
- dst[0] = ((lf >> 8) & 0xFF);
- dst[3] = (rf & 0xFF);
- dst[2] = ((rf >> 8) & 0xFF);
-
- dst[1 + 4] = (lr & 0xFF);
- dst[0 + 4] = ((lr >> 8) & 0xFF);
- dst[3 + 4] = (rr & 0xFF);
- dst[2 + 4] = ((rr >> 8) & 0xFF);
-
- dst[1 + 8] = (ce & 0xFF);
- dst[0 + 8] = ((ce >> 8) & 0xFF);
- dst[3 + 8] = (ce & 0xFF);
- dst[2 + 8] = ((ce >> 8) & 0xFF);
- }
- } else {
- for (i = cvt->len_cvt / 4; i; --i) {
- dst -= 12;
- src -= 4;
- lf = (Sint16) ((src[1] << 8) | src[0]);
- rf = (Sint16) ((src[3] << 8) | src[2]);
- ce = (lf / 2) + (rf / 2);
- rr = lf - ce;
- lr = rf - ce;
- dst[0] = (lf & 0xFF);
- dst[1] = ((lf >> 8) & 0xFF);
- dst[2] = (rf & 0xFF);
- dst[3] = ((rf >> 8) & 0xFF);
-
- dst[0 + 4] = (lr & 0xFF);
- dst[1 + 4] = ((lr >> 8) & 0xFF);
- dst[2 + 4] = (rr & 0xFF);
- dst[3 + 4] = ((rr >> 8) & 0xFF);
-
- dst[0 + 8] = (ce & 0xFF);
- dst[1 + 8] = ((ce >> 8) & 0xFF);
- dst[2 + 8] = (ce & 0xFF);
- dst[3 + 8] = ((ce >> 8) & 0xFF);
- }
- }
- }
- break;
-
- case AUDIO_S32:
- {
- Sint32 lf, rf, ce;
- const Uint32 *src = (const Uint32 *) (cvt->buf + cvt->len_cvt);
- Uint32 *dst = (Uint32 *) (cvt->buf + cvt->len_cvt * 3);
-
- if (SDL_AUDIO_ISBIGENDIAN(format)) {
- for (i = cvt->len_cvt / 8; i; --i) {
- dst -= 6;
- src -= 2;
- lf = (Sint32) SDL_SwapBE32(src[0]);
- rf = (Sint32) SDL_SwapBE32(src[1]);
- ce = (lf / 2) + (rf / 2);
- dst[0] = SDL_SwapBE32((Uint32) lf);
- dst[1] = SDL_SwapBE32((Uint32) rf);
- dst[2] = SDL_SwapBE32((Uint32) (lf - ce));
- dst[3] = SDL_SwapBE32((Uint32) (rf - ce));
- dst[4] = SDL_SwapBE32((Uint32) ce);
- dst[5] = SDL_SwapBE32((Uint32) ce);
- }
- } else {
- for (i = cvt->len_cvt / 8; i; --i) {
- dst -= 6;
- src -= 2;
- lf = (Sint32) SDL_SwapLE32(src[0]);
- rf = (Sint32) SDL_SwapLE32(src[1]);
- ce = (lf / 2) + (rf / 2);
- dst[0] = src[0];
- dst[1] = src[1];
- dst[2] = SDL_SwapLE32((Uint32) (lf - ce));
- dst[3] = SDL_SwapLE32((Uint32) (rf - ce));
- dst[4] = SDL_SwapLE32((Uint32) ce);
- dst[5] = SDL_SwapLE32((Uint32) ce);
- }
- }
- }
- break;
-
- case AUDIO_F32:
- {
- float lf, rf, ce;
- const float *src = (const float *) (cvt->buf + cvt->len_cvt);
- float *dst = (float *) (cvt->buf + cvt->len_cvt * 3);
-
- if (SDL_AUDIO_ISBIGENDIAN(format)) {
- for (i = cvt->len_cvt / 8; i; --i) {
- dst -= 6;
- src -= 2;
- lf = SDL_SwapFloatBE(src[0]);
- rf = SDL_SwapFloatBE(src[1]);
- ce = (lf * 0.5f) + (rf * 0.5f);
- dst[0] = src[0];
- dst[1] = src[1];
- dst[2] = SDL_SwapFloatBE(lf - ce);
- dst[3] = SDL_SwapFloatBE(rf - ce);
- dst[4] = dst[5] = SDL_SwapFloatBE(ce);
- }
- } else {
- for (i = cvt->len_cvt / 8; i; --i) {
- dst -= 6;
- src -= 2;
- lf = SDL_SwapFloatLE(src[0]);
- rf = SDL_SwapFloatLE(src[1]);
- ce = (lf * 0.5f) + (rf * 0.5f);
- dst[0] = src[0];
- dst[1] = src[1];
- dst[2] = SDL_SwapFloatLE(lf - ce);
- dst[3] = SDL_SwapFloatLE(rf - ce);
- dst[4] = dst[5] = SDL_SwapFloatLE(ce);
- }
- }
- }
- break;
-
- }
- cvt->len_cvt *= 3;
- if (cvt->filters[++cvt->filter_index]) {
- cvt->filters[cvt->filter_index] (cvt, format);
- }
-}
-
-
-/* Duplicate a stereo channel to a pseudo-4.0 stream */
-static void SDLCALL
-SDL_ConvertSurround_4(SDL_AudioCVT * cvt, SDL_AudioFormat format)
-{
- int i;
-
-#ifdef DEBUG_CONVERT
- fprintf(stderr, "Converting stereo to quad\n");
-#endif
-
- switch (format & (SDL_AUDIO_MASK_SIGNED |
- SDL_AUDIO_MASK_BITSIZE |
- SDL_AUDIO_MASK_DATATYPE)) {
- case AUDIO_U8:
- {
- Uint8 *src, *dst, lf, rf, ce;
-
- src = (Uint8 *) (cvt->buf + cvt->len_cvt);
- dst = (Uint8 *) (cvt->buf + cvt->len_cvt * 2);
- for (i = cvt->len_cvt; i; --i) {
- dst -= 4;
- src -= 2;
- lf = src[0];
- rf = src[1];
- ce = (lf / 2) + (rf / 2);
- dst[0] = lf;
- dst[1] = rf;
- dst[2] = lf - ce;
- dst[3] = rf - ce;
- }
- }
- break;
-
- case AUDIO_S8:
- {
- Sint8 *src, *dst, lf, rf, ce;
-
- src = (Sint8 *) cvt->buf + cvt->len_cvt;
- dst = (Sint8 *) cvt->buf + cvt->len_cvt * 2;
- for (i = cvt->len_cvt; i; --i) {
- dst -= 4;
- src -= 2;
- lf = src[0];
- rf = src[1];
- ce = (lf / 2) + (rf / 2);
- dst[0] = lf;
- dst[1] = rf;
- dst[2] = lf - ce;
- dst[3] = rf - ce;
- }
- }
- break;
-
- case AUDIO_U16:
- {
- Uint8 *src, *dst;
- Uint16 lf, rf, ce, lr, rr;
-
- src = cvt->buf + cvt->len_cvt;
- dst = cvt->buf + cvt->len_cvt * 2;
-
- if (SDL_AUDIO_ISBIGENDIAN(format)) {
- for (i = cvt->len_cvt / 4; i; --i) {
- dst -= 8;
- src -= 4;
- lf = (Uint16) ((src[0] << 8) | src[1]);
- rf = (Uint16) ((src[2] << 8) | src[3]);
- ce = (lf / 2) + (rf / 2);
- rr = lf - ce;
- lr = rf - ce;
- dst[1] = (lf & 0xFF);
- dst[0] = ((lf >> 8) & 0xFF);
- dst[3] = (rf & 0xFF);
- dst[2] = ((rf >> 8) & 0xFF);
-
- dst[1 + 4] = (lr & 0xFF);
- dst[0 + 4] = ((lr >> 8) & 0xFF);
- dst[3 + 4] = (rr & 0xFF);
- dst[2 + 4] = ((rr >> 8) & 0xFF);
- }
- } else {
- for (i = cvt->len_cvt / 4; i; --i) {
- dst -= 8;
- src -= 4;
- lf = (Uint16) ((src[1] << 8) | src[0]);
- rf = (Uint16) ((src[3] << 8) | src[2]);
- ce = (lf / 2) + (rf / 2);
- rr = lf - ce;
- lr = rf - ce;
- dst[0] = (lf & 0xFF);
- dst[1] = ((lf >> 8) & 0xFF);
- dst[2] = (rf & 0xFF);
- dst[3] = ((rf >> 8) & 0xFF);
-
- dst[0 + 4] = (lr & 0xFF);
- dst[1 + 4] = ((lr >> 8) & 0xFF);
- dst[2 + 4] = (rr & 0xFF);
- dst[3 + 4] = ((rr >> 8) & 0xFF);
- }
- }
- }
- break;
-
- case AUDIO_S16:
- {
- Uint8 *src, *dst;
- Sint16 lf, rf, ce, lr, rr;
-
- src = cvt->buf + cvt->len_cvt;
- dst = cvt->buf + cvt->len_cvt * 2;
-
- if (SDL_AUDIO_ISBIGENDIAN(format)) {
- for (i = cvt->len_cvt / 4; i; --i) {
- dst -= 8;
- src -= 4;
- lf = (Sint16) ((src[0] << 8) | src[1]);
- rf = (Sint16) ((src[2] << 8) | src[3]);
- ce = (lf / 2) + (rf / 2);
- rr = lf - ce;
- lr = rf - ce;
- dst[1] = (lf & 0xFF);
- dst[0] = ((lf >> 8) & 0xFF);
- dst[3] = (rf & 0xFF);
- dst[2] = ((rf >> 8) & 0xFF);
-
- dst[1 + 4] = (lr & 0xFF);
- dst[0 + 4] = ((lr >> 8) & 0xFF);
- dst[3 + 4] = (rr & 0xFF);
- dst[2 + 4] = ((rr >> 8) & 0xFF);
- }
- } else {
- for (i = cvt->len_cvt / 4; i; --i) {
- dst -= 8;
- src -= 4;
- lf = (Sint16) ((src[1] << 8) | src[0]);
- rf = (Sint16) ((src[3] << 8) | src[2]);
- ce = (lf / 2) + (rf / 2);
- rr = lf - ce;
- lr = rf - ce;
- dst[0] = (lf & 0xFF);
- dst[1] = ((lf >> 8) & 0xFF);
- dst[2] = (rf & 0xFF);
- dst[3] = ((rf >> 8) & 0xFF);
-
- dst[0 + 4] = (lr & 0xFF);
- dst[1 + 4] = ((lr >> 8) & 0xFF);
- dst[2 + 4] = (rr & 0xFF);
- dst[3 + 4] = ((rr >> 8) & 0xFF);
- }
- }
- }
- break;
-
- case AUDIO_S32:
- {
- const Uint32 *src = (const Uint32 *) (cvt->buf + cvt->len_cvt);
- Uint32 *dst = (Uint32 *) (cvt->buf + cvt->len_cvt * 2);
- Sint32 lf, rf, ce;
-
- if (SDL_AUDIO_ISBIGENDIAN(format)) {
- for (i = cvt->len_cvt / 8; i; --i) {
- dst -= 4;
- src -= 2;
- lf = (Sint32) SDL_SwapBE32(src[0]);
- rf = (Sint32) SDL_SwapBE32(src[1]);
- ce = (lf / 2) + (rf / 2);
- dst[0] = src[0];
- dst[1] = src[1];
- dst[2] = SDL_SwapBE32((Uint32) (lf - ce));
- dst[3] = SDL_SwapBE32((Uint32) (rf - ce));
- }
- } else {
- for (i = cvt->len_cvt / 8; i; --i) {
- dst -= 4;
- src -= 2;
- lf = (Sint32) SDL_SwapLE32(src[0]);
- rf = (Sint32) SDL_SwapLE32(src[1]);
- ce = (lf / 2) + (rf / 2);
- dst[0] = src[0];
- dst[1] = src[1];
- dst[2] = SDL_SwapLE32((Uint32) (lf - ce));
- dst[3] = SDL_SwapLE32((Uint32) (rf - ce));
- }
- }
- }
- break;
-
- case AUDIO_F32:
- {
- const float *src = (const float *) (cvt->buf + cvt->len_cvt);
- float *dst = (float *) (cvt->buf + cvt->len_cvt * 2);
- float lf, rf, ce;
-
- if (SDL_AUDIO_ISBIGENDIAN(format)) {
- for (i = cvt->len_cvt / 8; i; --i) {
- dst -= 4;
- src -= 2;
- lf = SDL_SwapFloatBE(src[0]);
- rf = SDL_SwapFloatBE(src[1]);
- ce = (lf / 2) + (rf / 2);
- dst[0] = src[0];
- dst[1] = src[1];
- dst[2] = SDL_SwapFloatBE(lf - ce);
- dst[3] = SDL_SwapFloatBE(rf - ce);
- }
- } else {
- for (i = cvt->len_cvt / 8; i; --i) {
- dst -= 4;
- src -= 2;
- lf = SDL_SwapFloatLE(src[0]);
- rf = SDL_SwapFloatLE(src[1]);
- ce = (lf / 2) + (rf / 2);
- dst[0] = src[0];
- dst[1] = src[1];
- dst[2] = SDL_SwapFloatLE(lf - ce);
- dst[3] = SDL_SwapFloatLE(rf - ce);
- }
- }
- }
- break;
- }
- cvt->len_cvt *= 2;
- if (cvt->filters[++cvt->filter_index]) {
- cvt->filters[cvt->filter_index] (cvt, format);
- }
-}
-
-
-int
-SDL_ConvertAudio(SDL_AudioCVT * cvt)
-{
- /* !!! FIXME: (cvt) should be const; stack-copy it here. */
- /* !!! FIXME: (actually, we can't...len_cvt needs to be updated. Grr.) */
-
- /* Make sure there's data to convert */
- if (cvt->buf == NULL) {
- SDL_SetError("No buffer allocated for conversion");
- return (-1);
- }
- /* Return okay if no conversion is necessary */
- cvt->len_cvt = cvt->len;
- if (cvt->filters[0] == NULL) {
- return (0);
- }
-
- /* Set up the conversion and go! */
- cvt->filter_index = 0;
- cvt->filters[0] (cvt, cvt->src_format);
- return (0);
-}
-
-
-static SDL_AudioFilter
-SDL_HandTunedTypeCVT(SDL_AudioFormat src_fmt, SDL_AudioFormat dst_fmt)
-{
- /*
- * Fill in any future conversions that are specialized to a
- * processor, platform, compiler, or library here.
- */
-
- return NULL; /* no specialized converter code available. */
-}
-
-
-/*
- * Find a converter between two data types. We try to select a hand-tuned
- * asm/vectorized/optimized function first, and then fallback to an
- * autogenerated function that is customized to convert between two
- * specific data types.
- */
-static int
-SDL_BuildAudioTypeCVT(SDL_AudioCVT * cvt,
- SDL_AudioFormat src_fmt, SDL_AudioFormat dst_fmt)
-{
- if (src_fmt != dst_fmt) {
- const Uint16 src_bitsize = SDL_AUDIO_BITSIZE(src_fmt);
- const Uint16 dst_bitsize = SDL_AUDIO_BITSIZE(dst_fmt);
- SDL_AudioFilter filter = SDL_HandTunedTypeCVT(src_fmt, dst_fmt);
-
- /* No hand-tuned converter? Try the autogenerated ones. */
- if (filter == NULL) {
- int i;
- for (i = 0; sdl_audio_type_filters[i].filter != NULL; i++) {
- const SDL_AudioTypeFilters *filt = &sdl_audio_type_filters[i];
- if ((filt->src_fmt == src_fmt) && (filt->dst_fmt == dst_fmt)) {
- filter = filt->filter;
- break;
- }
- }
-
- if (filter == NULL) {
- SDL_SetError("No conversion available for these formats");
- return -1;
- }
- }
-
- /* Update (cvt) with filter details... */
- cvt->filters[cvt->filter_index++] = filter;
- if (src_bitsize < dst_bitsize) {
- const int mult = (dst_bitsize / src_bitsize);
- cvt->len_mult *= mult;
- cvt->len_ratio *= mult;
- } else if (src_bitsize > dst_bitsize) {
- cvt->len_ratio /= (src_bitsize / dst_bitsize);
- }
-
- return 1; /* added a converter. */
- }
-
- return 0; /* no conversion necessary. */
-}
-
-
-static SDL_AudioFilter
-SDL_HandTunedResampleCVT(SDL_AudioCVT * cvt, int dst_channels,
- int src_rate, int dst_rate)
-{
- /*
- * Fill in any future conversions that are specialized to a
- * processor, platform, compiler, or library here.
- */
-
- return NULL; /* no specialized converter code available. */
-}
-
-static int
-SDL_FindFrequencyMultiple(const int src_rate, const int dst_rate)
-{
- int retval = 0;
-
- /* If we only built with the arbitrary resamplers, ignore multiples. */
-#if !LESS_RESAMPLERS
- int lo, hi;
- int div;
-
- SDL_assert(src_rate != 0);
- SDL_assert(dst_rate != 0);
- SDL_assert(src_rate != dst_rate);
-
- if (src_rate < dst_rate) {
- lo = src_rate;
- hi = dst_rate;
- } else {
- lo = dst_rate;
- hi = src_rate;
- }
-
- /* zero means "not a supported multiple" ... we only do 2x and 4x. */
- if ((hi % lo) != 0)
- return 0; /* not a multiple. */
-
- div = hi / lo;
- retval = ((div == 2) || (div == 4)) ? div : 0;
-#endif
-
- return retval;
-}
-
-static int
-SDL_BuildAudioResampleCVT(SDL_AudioCVT * cvt, int dst_channels,
- int src_rate, int dst_rate)
-{
- if (src_rate != dst_rate) {
- SDL_AudioFilter filter = SDL_HandTunedResampleCVT(cvt, dst_channels,
- src_rate, dst_rate);
-
- /* No hand-tuned converter? Try the autogenerated ones. */
- if (filter == NULL) {
- int i;
- const int upsample = (src_rate < dst_rate) ? 1 : 0;
- const int multiple =
- SDL_FindFrequencyMultiple(src_rate, dst_rate);
-
- for (i = 0; sdl_audio_rate_filters[i].filter != NULL; i++) {
- const SDL_AudioRateFilters *filt = &sdl_audio_rate_filters[i];
- if ((filt->fmt == cvt->dst_format) &&
- (filt->channels == dst_channels) &&
- (filt->upsample == upsample) &&
- (filt->multiple == multiple)) {
- filter = filt->filter;
- break;
- }
- }
-
- if (filter == NULL) {
- SDL_SetError("No conversion available for these rates");
- return -1;
- }
- }
-
- /* Update (cvt) with filter details... */
- cvt->filters[cvt->filter_index++] = filter;
- if (src_rate < dst_rate) {
- const double mult = ((double) dst_rate) / ((double) src_rate);
- cvt->len_mult *= (int) SDL_ceil(mult);
- cvt->len_ratio *= mult;
- } else {
- cvt->len_ratio /= ((double) src_rate) / ((double) dst_rate);
- }
-
- return 1; /* added a converter. */
- }
-
- return 0; /* no conversion necessary. */
-}
-
-
-/* Creates a set of audio filters to convert from one format to another.
- Returns -1 if the format conversion is not supported, 0 if there's
- no conversion needed, or 1 if the audio filter is set up.
-*/
-
-int
-SDL_BuildAudioCVT(SDL_AudioCVT * cvt,
- SDL_AudioFormat src_fmt, Uint8 src_channels, int src_rate,
- SDL_AudioFormat dst_fmt, Uint8 dst_channels, int dst_rate)
-{
- /*
- * !!! FIXME: reorder filters based on which grow/shrink the buffer.
- * !!! FIXME: ideally, we should do everything that shrinks the buffer
- * !!! FIXME: first, so we don't have to process as many bytes in a given
- * !!! FIXME: filter and abuse the CPU cache less. This might not be as
- * !!! FIXME: good in practice as it sounds in theory, though.
- */
-
- /* Sanity check target pointer */
- if (cvt == NULL) {
- return SDL_InvalidParamError("cvt");
- }
-
- /* there are no unsigned types over 16 bits, so catch this up front. */
- if ((SDL_AUDIO_BITSIZE(src_fmt) > 16) && (!SDL_AUDIO_ISSIGNED(src_fmt))) {
- return SDL_SetError("Invalid source format");
- }
- if ((SDL_AUDIO_BITSIZE(dst_fmt) > 16) && (!SDL_AUDIO_ISSIGNED(dst_fmt))) {
- return SDL_SetError("Invalid destination format");
- }
-
- /* prevent possible divisions by zero, etc. */
- if ((src_channels == 0) || (dst_channels == 0)) {
- return SDL_SetError("Source or destination channels is zero");
- }
- if ((src_rate == 0) || (dst_rate == 0)) {
- return SDL_SetError("Source or destination rate is zero");
- }
-#ifdef DEBUG_CONVERT
- printf("Build format %04x->%04x, channels %u->%u, rate %d->%d\n",
- src_fmt, dst_fmt, src_channels, dst_channels, src_rate, dst_rate);
-#endif
-
- /* Start off with no conversion necessary */
- SDL_zerop(cvt);
- cvt->src_format = src_fmt;
- cvt->dst_format = dst_fmt;
- cvt->needed = 0;
- cvt->filter_index = 0;
- cvt->filters[0] = NULL;
- cvt->len_mult = 1;
- cvt->len_ratio = 1.0;
- cvt->rate_incr = ((double) dst_rate) / ((double) src_rate);
-
- /* Convert data types, if necessary. Updates (cvt). */
- if (SDL_BuildAudioTypeCVT(cvt, src_fmt, dst_fmt) == -1) {
- return -1; /* shouldn't happen, but just in case... */
- }
-
- /* Channel conversion */
- if (src_channels != dst_channels) {
- if ((src_channels == 1) && (dst_channels > 1)) {
- cvt->filters[cvt->filter_index++] = SDL_ConvertStereo;
- cvt->len_mult *= 2;
- src_channels = 2;
- cvt->len_ratio *= 2;
- }
- if ((src_channels == 2) && (dst_channels == 6)) {
- cvt->filters[cvt->filter_index++] = SDL_ConvertSurround;
- src_channels = 6;
- cvt->len_mult *= 3;
- cvt->len_ratio *= 3;
- }
- if ((src_channels == 2) && (dst_channels == 4)) {
- cvt->filters[cvt->filter_index++] = SDL_ConvertSurround_4;
- src_channels = 4;
- cvt->len_mult *= 2;
- cvt->len_ratio *= 2;
- }
- while ((src_channels * 2) <= dst_channels) {
- cvt->filters[cvt->filter_index++] = SDL_ConvertStereo;
- cvt->len_mult *= 2;
- src_channels *= 2;
- cvt->len_ratio *= 2;
- }
- if ((src_channels == 6) && (dst_channels <= 2)) {
- cvt->filters[cvt->filter_index++] = SDL_ConvertStrip;
- src_channels = 2;
- cvt->len_ratio /= 3;
- }
- if ((src_channels == 6) && (dst_channels == 4)) {
- cvt->filters[cvt->filter_index++] = SDL_ConvertStrip_2;
- src_channels = 4;
- cvt->len_ratio /= 2;
- }
- /* This assumes that 4 channel audio is in the format:
- Left {front/back} + Right {front/back}
- so converting to L/R stereo works properly.
- */
- while (((src_channels % 2) == 0) &&
- ((src_channels / 2) >= dst_channels)) {
- cvt->filters[cvt->filter_index++] = SDL_ConvertMono;
- src_channels /= 2;
- cvt->len_ratio /= 2;
- }
- if (src_channels != dst_channels) {
- /* Uh oh.. */ ;
- }
- }
-
- /* Do rate conversion, if necessary. Updates (cvt). */
- if (SDL_BuildAudioResampleCVT(cvt, dst_channels, src_rate, dst_rate) ==
- -1) {
- return -1; /* shouldn't happen, but just in case... */
- }
-
- /* Set up the filter information */
- if (cvt->filter_index != 0) {
- cvt->needed = 1;
- cvt->src_format = src_fmt;
- cvt->dst_format = dst_fmt;
- cvt->len = 0;
- cvt->buf = NULL;
- cvt->filters[cvt->filter_index] = NULL;
- }
- return (cvt->needed);
-}
-
-
-/* vi: set ts=4 sw=4 expandtab: */